Evaluating documentation of social history in paediatric medical notes at a regional paediatric centre - a quality improvement initiative.

BACKGROUND: A child's home and family environment plays a vital role in neuro-cognitive and emotional development. Assessment of a child's home environment and social circumstances is an crucial part of holistic Paediatric assessment. AIMS: Our aim is to achieve full compliance with comprehensive documentation of biopsychosocial history, for all children medically admitted to the children's inpatient unit in University Hospital Limerick. METHODS: We performed a retrospective chart review to audit documentation within our department. This was followed by teaching interventions and a survey on knowledge, attitudes and behaviour of paediatric non-consultant hospital doctors (NCHDs) towards the social history. We performed two subsequent re-audits to assess response to our interventions, and provided educational sessions to seek improvement in quality of care. RESULTS: Results showed a significant improvement in quality of documentation following interventions, demonstrated by a net increase of 53% in levels of documentation of some social history on first re-audit. Though this was not maintained at an optimum level throughout the course of the year with compliance reduced from 95% to 82.5% on second re-audit, there was nonetheless a sustained improvement from our baseline. Our qualitative survey suggested further initiatives and educational tools that may be helpful in supporting the ongoing optimisation of the quality of documentation of social history in our paediatric department. CONCLUSION: We hope this quality improvement initiative will ultimately lead to sustained improvements in the quality of patient-centred care, and early identification and intervention for children at risk in our community.

Dynamics of silver elution from functionalised antimicrobial nanofiltration membranes.

In an effort to mitigate biofouling on thin film composite membranes such as nanofiltration and reverse osmosis, a myriad of different surface modification strategies has been published. The use of silver nanoparticles (Ag-NPs) has emerged as being particularly promising. Nevertheless, the stability of these surface modifications is still poorly understood, particularly under permeate flux conditions. Leaching or elution of Ag-NPs from the membrane surface can not only affect the antimicrobial characteristics of the membrane, but could also potentially present an environmental liability when applied in industrial-scale systems. This study sought to investigate the dynamics of silver elution and the bactericidal effect of an Ag-NP functionalised NF270 membrane. Inductively coupled plasma-atomic emission spectroscopy was used to show that the bulk of leached silver occurred at the start of experimental runs, and was found to be independent of salt or permeate conditions used. Cumulative amounts of leached silver did, however, stabilise following the initial release, and were shown to have maintained the biocidal characteristics of the modified membrane, as observed by a higher fraction of structurally damaged Pseudomonas fluorescens cells. These results highlight the need to comprehensively assess the time-dependent nature of bactericidal membranes.

The criterion-referenced validity of the FITNESSGRAM Trunk-Extension test.

AIM: The purpose of this study was to test utility of different fitness field tests to predict self-reported low-back pain (LBP) in youth. METHODS: A sample of 376 school aged (4th through 10th grade students) first completed a survey instrument designed to assess past events (and degree) of LBP. On subsequent days, participants completed a battery of different muscular fitness tests including the current FITNESSGRAM trunk extension test. Receiver operator characteristic curves (ROC) were used to test the utility of single and combined scores from various tests to predict self-reported LBP. RESULTS: The results show that the trunk extension test used in FITNESSGRAM has poor utility for predicting self-reported LBP. In girls, the sit-and-reach, the static curl-up test, and a composite score using static and dynamic curl-up scores had the highest Area Under the Curve (AUC=0.80, 0.71, and 0.79, respectively). Sensitivity (Se) values ranged from 75.0-85.7 while Specificity (Sp) ranged from 59.1-81.4. In boys, the dynamic curl-up test alone was the best predictor of LBP in high-school boys (AUC=0.75, Sensitivity=75.0 and Specificity=74.1). CONCLUSION: The reasonable Sensitivity values from the ROC analyses indicate that individual and aggregate indicators of musculoskeletal fitness can potentially identify girls that had LBP in the past. However, the low values for Specificity indicates that girls with "No LBP" can be misclassified as being at risk for LBP. The current FITNESSGRAM trunk extension test was not able to discriminate between students with and without LBP therefore, the utility of this test for fitness assessment in youth should be revisited.

A new aberration-corrected, energy-filtered LEEM/PEEM instrument II. Operation and results.

In Part I we described a new design for an aberration-corrected Low Energy Electron Microscope (LEEM) and Photo Electron Emission Microscope (PEEM) equipped with an in-line electron energy filter. The chromatic and spherical aberrations of the objective lens are corrected with an electrostatic electron mirror that provides independent control of the chromatic and spherical aberration coefficients Cc and C3, as well as the mirror focal length. In this Part II we discuss details of microscope operation, how the microscope is set up in a systematic fashion, and we present typical results.

Direct measurement of the growth mode of graphene on SiC(0001) and SiC(0001¯).

We have determined the growth mode of graphene on SiC(0001) and SiC(0001¯) using ultrathin, isotopically labeled Si(13)C "marker layers" grown epitaxially on the Si(12)C surfaces. Few-layer graphene overlayers were formed via thermal decomposition at elevated temperature. For both surface terminations (Si face and C face), we find that the (13)C is located mainly in the outermost graphene layers, indicating that, during decomposition, new graphene layers form underneath existing ones.

Atomic-scale transport in epitaxial graphene.

The high carrier mobility of graphene is key to its applications, and understanding the factors that limit mobility is essential for future devices. Yet, despite significant progress, mobilities in excess of the 2×10(5) cm(2) V(-1) s(-1) demonstrated in free-standing graphene films have not been duplicated in conventional graphene devices fabricated on substrates. Understanding the origins of this degradation is perhaps the main challenge facing graphene device research. Experiments that probe carrier scattering in devices are often indirect, relying on the predictions of a specific model for scattering, such as random charged impurities in the substrate. Here, we describe model-independent, atomic-scale transport measurements that show that scattering at two key defects--surface steps and changes in layer thickness--seriously degrades transport in epitaxial graphene films on SiC. These measurements demonstrate the strong impact of atomic-scale substrate features on graphene performance.

Effect of exopolysaccharide produced by isogenic strains of Lactococcus lactis on half-fat Cheddar cheese.

Fat-reduced cheeses often suffer from undesirable texture, flavor, and cooking properties. Exopolysaccharides (EPS) produced by starter strains have been proposed as a mechanism to increase yield and to improve the texture and cooking properties of reduced-fat cheeses. The objective of this work was to assess the influence of an exopolysaccharide on the yield, texture, cooking properties, and quality of half-fat Cheddar cheese. Two pilot-scale half-fat Cheddar cheeses were manufactured using single starters of an isogenic strain of Lactococcus lactis ssp. cremoris (DPC6532 and DPC6533) that differed in their ability to produce exopolysaccharide. Consequently, any differences detected between the cheeses were attributed to the presence of the exopolysaccharide. The results indicated that cheeses made with the exopolysaccharide-producing starter had an 8.17% increase in actual cheese yield (per 100 kg of milk), a 9.49% increase in moisture content, increase in water activity and water desorption rate at relative humidities

A new aberration-corrected, energy-filtered LEEM/PEEM instrument. I. Principles and design.

We describe a new design for an aberration-corrected low energy electron microscope (LEEM) and photo electron emission microscope (PEEM), equipped with an in-line electron energy filter. The chromatic and spherical aberrations of the objective lens are corrected with an electrostatic electron mirror that provides independent control over the chromatic and spherical aberration coefficients C(c) and C(3), as well as the mirror focal length, to match and correct the aberrations of the objective lens. For LEEM (PEEM) the theoretical resolution is calculated to be approximately 1.5 nm (approximately 4 nm). Unlike previous designs, this instrument makes use of two magnetic prism arrays to guide the electron beam from the sample to the electron mirror, removing chromatic dispersion in front of the mirror by symmetry. The aberration correction optics was retrofitted to an uncorrected instrument with a base resolution of 4.1 nm in LEEM. Initial results in LEEM show an improvement in resolution to approximately 2 nm.

Thermodynamics and kinetics of graphene growth on SiC(0001).

The formation of surface phases on the Si-terminated SiC(0001) surface, from the Si-rich (3x3) structure, through the intermediate (1x1) and (sqrt[3]xsqrt[3])-R30 degrees structures, to the C-rich (6sqrt[3]x6sqrt[3]) phase, and finally epitaxial graphene, has been well documented. But the thermodynamics and kinetics of these phase formations are poorly understood. Using in situ low energy electron microscopy, we show how the phase transformation temperatures can be shifted over several hundred degrees Celsius, and the phase transformation time scales reduced by several orders of magnitude, by balancing the rate of Si evaporation with an external flux of Si. Detailed insight in the thermodynamics allows us to dramatically improve the morphology of the final C-rich surface phases, including epitaxial graphene.

A simple energy filter for low energy electron microscopy/photoelectron emission microscopy instruments.

Addition of an electron energy filter to low energy electron microscopy (LEEM) and photoelectron emission microscopy (PEEM) instruments greatly improves their analytical capabilities. However, such filters tend to be quite complex, both electron optically and mechanically. Here we describe a simple energy filter for the existing IBM LEEM/PEEM instrument, which is realized by adding a single scanning aperture slit to the objective transfer optics, without any further modifications to the microscope. This energy filter displays a very high energy resolution ΔE/E = 2 × 10(-5), and a non-isochromaticity of ∼0.5 eV/10 µm. The setup is capable of recording selected area electron energy spectra and angular distributions at 0.15 eV energy resolution, as well as energy filtered images with a 1.5 eV energy pass band at an estimated spatial resolution of ∼10 nm. We demonstrate the use of this energy filter in imaging and spectroscopy of surfaces using a laboratory-based He I (21.2 eV) light source, as well as imaging of Ag nanowires on Si(001) using the 4 eV energy loss Ag plasmon.

Spontaneous formation and growth of a new polytype on SiC(0001).

Using in situ electron microscopy, we have measured the structure of SiC(0001)-4H during annealing in vacuum. Above 1000 degrees C, an additional SiC bilayer forms on the surface that changes the polytype from hexagonal (4H) to cubic (3C). The interaction with surface steps prevents the cubic layer from growing thicker: the new phase does not wet the steps of the underlying 4H substrate. Instead, the cubic layer expands laterally, accelerating step bunching in the surrounding hexagonal regions. During SiC homoepitaxy, this lack of step edge wetting leads to the growth of 3C twins separated by deep grooves.

Metastability in 2D self-assembling systems.

We show that 2D self-assembled domains can remain trapped in a large variety of long-lived and metastable shapes that arise from an interplay of crystalline anisotropy and relaxation of elastic strain. On commonly used cubic (111) substrates, these shapes include extended or stacked structures made up of triangular domains connected at their corners, compact shapes with both convex and concave curvatures and others with narrow and elongated arms. We show that all of these distinct experimentally observed shapes can be explained within a unified framework and present a phase diagram that systematically classifies the metastable shapes as a function of their size.

Production of ingredient-type cheddar cheese with accelerated flavor development by addition of enzyme-modified cheese powder.

Fast-ripened Cheddar cheeses for ingredient purposes were produced by addition of a dried enzyme-modified cheese (EMC; 0.25 and 1 g/100 g of milled curd) at the salting stage during a standard Cheddar cheese-making procedure. Populations of starter and nonstarter lactic acid bacteria (NSLAB), levels of proteolysis and lipolysis, volatile analysis, and flavor development (by quantitative descriptive sensory analysis) were monitored over a 6-mo ripening period. Levels of free AA and free fatty acids were elevated in the experimental cheeses on d 1 because of inclusion of the EMC. Counts of NSLAB were also elevated in the experimental cheeses compared with the control cheese from the start of ripening. Levels of free AA were slightly elevated in the experimental cheeses at 1, 2, and 4 mo, but significantly greater accumulations were detected by 6 mo of ripening, with His, Leu, and glutamate reflecting the greatest increases. Levels of long-chain free fatty acids increased up to 2 mo, indicating an initial stimulation of lipolysis, but had decreased by 6 mo, indicating greater catabolism, probably caused by NSLAB and increased starter lysis. Principal component analysis of the volatile compounds showed few differences in the aroma profiles among the cheeses up to 4 mo of ripening, but a large separation of the cheeses supplemented with EMC relative to the control was observed by 6 mo. Sensory analysis of the cheeses with added EMC showed an acceleration of 2 mo in flavor development compared with the control cheese with the addition of 1 g/100 g of EMC developing a flavor profile at 4 mo similar to the control cheese at 6 mo of ripening. However, atypical Cheddar flavors developed on prolonged storage. This study shows the potential of adding EMC during Cheddar production to produce a fast-ripened ingredient-type Cheddar cheese.

Anomalous spiral motion of steps near dislocations on silicon surfaces.

We have used low-energy electron microscopy to measure step motion on Si(111) and Si(001) near dislocations during growth and sublimation. Steps on Si(111) exhibit the classic rotating Archimedean spiral motion, as predicted by Burton, Cabrera, and Frank. Steps on Si(001), however, move in a strikingly different manner. The strain-relieving anomalous behavior can be understood in detail by considering how the local step velocity is affected by the nonuniform strain field arising from the dislocation. We show how the dynamic step-flow pattern is related to the dislocation slip system.

Origins of nanoscale heterogeneity in ultrathin films.

A key challenge in thin-film growth is controlling structure and composition at the atomic scale. We have used spatially resolved electron scattering to measure how the three-dimensional composition profile of an alloy film evolves with time at the nanometer length scale. We show that heterogeneity during the growth of Pd on Cu(001) arises naturally from a generic step-overgrowth mechanism relevant in many growth systems.

Altering renneting pH changes microstructure, cell distribution, and lysis of Lactococcus lactis AM2 in cheese made from ultrafiltered milk.

The objective of this study was to investigate the lysis of a highly autolytic strain of Lactococcus lactis ssp. cremoris AM2 in a model cheese made from concentrated ultrafiltered milk. From the same initial ultrafiltered retentate inoculated with L. lactis AM2, 5 cheeses were made by the addition of rennet at different pH values (6.6, 6.2, 5.8, 5.4, and 5.2). Lysis was monitored by measurement of the release of lactate dehydrogenase, an intracellular marker enzyme, and by immunodetection of intracellular proteins with species-specific antibodies. Confocal scanning laser microscopy (CSLM) was used to investigate the cheese microstructure by staining for protein and fat. Dual staining with a bacterial viability kit with CSLM was performed to reveal the integrity and localization of the bacterial cells. Levels of soluble calcium significantly increased when the pH at which the rennet was added decreased. In cheese renneted at pH 6.6, CSLM revealed an open porous structure containing a dense protein network with fat globules of different sizes distributed in the aqueous phase. In cheese renneted at pH 5.2, the protein network was homogeneous, with a less dense protein network, and an even distribution of fat globules. On d 1, bacterial cells were organized into colonies in cheese renneted at pH 6.6, whereas in cheeses renneted at pH 5.2, bacteria were evenly dispersed as single cells throughout the protein network. Lysis was detected on d 1 in cheeses renneted at high pH values and continued to increase throughout ripening, whereas induction of lysis was delayed in cheeses renneted at lower pH values until the end of ripening. This study demonstrates that alterations in the microstructure of the cheese and the distribution of cells play a role in lysis induction of L. lactis AM2.

The influence of the surface migration of gold on the growth of silicon nanowires.

Interest in nanowires continues to grow, fuelled in part by applications in nanotechnology. The ability to engineer nanowire properties makes them especially promising in nanoelectronics. Most silicon nanowires are grown using the vapour-liquid-solid (VLS) mechanism, in which the nanowire grows from a gold/silicon catalyst droplet during silicon chemical vapour deposition. Despite over 40 years of study, many aspects of VLS growth are not well understood. For example, in the conventional picture the catalyst droplet does not change during growth, and the nanowire sidewalls consist of clean silicon facets. Here we demonstrate that these assumptions are false for silicon nanowires grown on Si(111) under conditions where all of the experimental parameters (surface structure, gas cleanliness, and background contaminants) are carefully controlled. We show that gold diffusion during growth determines the length, shape, and sidewall properties of the nanowires. Gold from the catalyst droplets wets the nanowire sidewalls, eventually consuming the droplets and terminating VLS growth. Gold diffusion from the smaller droplets to the larger ones (Ostwald ripening) leads to nanowire diameters that change during growth. These results show that the silicon nanowire growth is fundamentally limited by gold diffusion: smooth, arbitrarily long nanowires cannot be grown without eliminating gold migration.

Selective placement of carbon nanotubes on metal-oxide surfaces.

We describe a method to selectively position carbon nanotubes on Al2O3 and HfO2 surfaces. The method exploits the selective binding of alkylphosphonic acids to oxide surfaces with large isoelectric points (i.e. basic rather than acidic surfaces). We have patterned oxide surfaces with acids using both microcontact printing and conventional lithography. With proper choice of the functional end group (e.g., -CH3 or -NH2), nanotube adhesion to the surface can be either prevented or enhanced.